Excessive daytime sleepiness (EDS) is a common complaint. According to the National Sleep Foundation 2000 Omnibus Sleep in America Poll: a sizable proportion of adults (43%) report that they are so sleepy during the day that it interferes with their dailyactivities a few days per month or more; and, one out of five (20%) experience this level of daytime sleepiness at least a few days per week or more.
EDS reduces personal effectiveness at school or work. Each year in the United States >50,000 motor vehicle accidents areattributed to driving while sleepy.
The most common cause of daytime sleepiness is insufficient sleep, which may reflect poor sleep hygiene (behaviors impacting sleep) or self-imposed or socially dictated sleep deprivation. Sleep-related breathing disorders and Periodic limb movements of sleep are also very common causes of daytime sleepiness. A variety of medical conditions may be associated with sleep fragmentation,including arthritis, fibromyalgia, spondylosis, chronic pain of any nature, asthma and chronic obstructive pulmonary disease.
The Epworth Sleepiness Scale is a questionnaire to assess overall sleepiness. A total score of 10 or more is abnormal. For objective assessment of sleepiness, the Multiple Sleep Latency Test (MSLT) is performed immediately after an overnight polysomnogram (to ensure adequate sleep during the prior night and to exclude obvious causes of nocturnal sleep disruption, which would explain the daytime symptoms). On the MSLT, mean sleep latency >10 min is considered normal.
Pharmacotherapy is generally achieved with stimulants, such as amphetamine sulfate and methylphenidate or alerting agents
such as modafinil.